it's not just you...I have an MMP2 and an audiophile and I can't get a thing out of it into my Audiophile 2496 or my Emu 1280 via spdif. At my school, I also tried hooking it up to a DAT recorder and a Pro Tools mbox and a bona fide pro tools TDM rig. No go.
BUT...here's the kicker. The exact same unit works on a digital mixer and some digital speakers at the music store I bought it at. This is actually the second MMP I've owned and still can't get working SPDIF out.
I also tried the AES/EBU out...that works fine. Just that spdif that's annoying.
Neither Roland nor M-audio tech support has been able to figure out anything.